Conventionally, a system to photograph a fingerprint of a finger pressed onto the surface of a prism with a video camera disposed under the surface of the prism is well-known in the art. Photographed image data of the fingerprint is inputted to a computer to be compared with fingerprints (master data) stored in a memory. Here, it is preferable that the image data of fingerprint is as clear as possible. However, the data may not be clear enough due to the given pressure of a finger to the prism or perspiration on the surface of the finger. Therefore, it is necessary to properly select the data provided for the verification to the computer.
The present invention solves the above problems of the prior art and has an object to provide a fingerprint photographing system which obtains an image data of a clear fingerprint for fingerprint verification.